Our goal in writing qemu_strtoi() and friends is to have an interface harder to abuse than libc's strtol(). Leaving the return value initialized on some error paths does not lend itself well to this goal; and our documentation wasn't helpful on the matter.
Note that the previous patch changed all qemu_strtosz() EINVAL error paths to slam value to 0 rather than stay uninitialized, even when the EINVAL eror occurs because of trailing junk. But for the remaining integral qemu_strto*, it's easier to return the parsed value than to force things back to zero, in part because of how check_strtox_error works; and doing so creates less churn in the testsuite. Here, the list of affected callers is much longer ('git grep "qemu_strto[ui]" *.c **/*.c | grep -v tests/ |wc -l' outputs 87, although a few of those are the implementation in in cutils.c), so touching as little as possible is the wisest course of action. Signed-off-by: Eric Blake <ebl...@redhat.com> --- tests/unit/test-cutils.c | 24 +++++++++++------------ util/cutils.c | 42 +++++++++++++++++++++++++--------------- 2 files changed, 38 insertions(+), 28 deletions(-) diff --git a/tests/unit/test-cutils.c b/tests/unit/test-cutils.c index 9cf00a810e4..2cb33e41ae4 100644 --- a/tests/unit/test-cutils.c +++ b/tests/unit/test-cutils.c @@ -250,7 +250,7 @@ static void test_qemu_strtoi_null(void) err = qemu_strtoi(NULL, &endptr, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpint(res, ==, 999); + g_assert_cmpint(res, ==, 0); g_assert_null(endptr); } @@ -479,7 +479,7 @@ static void test_qemu_strtoi_full_null(void) err = qemu_strtoi(NULL, &endptr, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpint(res, ==, 999); + g_assert_cmpint(res, ==, 0); g_assert_null(endptr); } @@ -557,7 +557,7 @@ static void test_qemu_strtoui_null(void) err = qemu_strtoui(NULL, &endptr, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpuint(res, ==, 999); + g_assert_cmpuint(res, ==, 0); g_assert_null(endptr); } @@ -784,7 +784,7 @@ static void test_qemu_strtoui_full_null(void) err = qemu_strtoui(NULL, NULL, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpuint(res, ==, 999); + g_assert_cmpuint(res, ==, 0); } static void test_qemu_strtoui_full_empty(void) @@ -860,7 +860,7 @@ static void test_qemu_strtol_null(void) err = qemu_strtol(NULL, &endptr, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpint(res, ==, 999); + g_assert_cmpint(res, ==, 0); g_assert_null(endptr); } @@ -1087,7 +1087,7 @@ static void test_qemu_strtol_full_null(void) err = qemu_strtol(NULL, &endptr, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpint(res, ==, 999); + g_assert_cmpint(res, ==, 0); g_assert_null(endptr); } @@ -1165,7 +1165,7 @@ static void test_qemu_strtoul_null(void) err = qemu_strtoul(NULL, &endptr, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpuint(res, ==, 999); + g_assert_cmpuint(res, ==, 0); g_assert_null(endptr); } @@ -1390,7 +1390,7 @@ static void test_qemu_strtoul_full_null(void) err = qemu_strtoul(NULL, NULL, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpuint(res, ==, 999); + g_assert_cmpuint(res, ==, 0); } static void test_qemu_strtoul_full_empty(void) @@ -1466,7 +1466,7 @@ static void test_qemu_strtoi64_null(void) err = qemu_strtoi64(NULL, &endptr, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpint(res, ==, 999); + g_assert_cmpint(res, ==, 0); g_assert_null(endptr); } @@ -1691,7 +1691,7 @@ static void test_qemu_strtoi64_full_null(void) err = qemu_strtoi64(NULL, NULL, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpint(res, ==, 999); + g_assert_cmpint(res, ==, 0); } static void test_qemu_strtoi64_full_empty(void) @@ -1769,7 +1769,7 @@ static void test_qemu_strtou64_null(void) err = qemu_strtou64(NULL, &endptr, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpuint(res, ==, 999); + g_assert_cmpuint(res, ==, 0); g_assert_null(endptr); } @@ -1994,7 +1994,7 @@ static void test_qemu_strtou64_full_null(void) err = qemu_strtou64(NULL, NULL, 0, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert_cmpuint(res, ==, 999); + g_assert_cmpuint(res, ==, 0); } static void test_qemu_strtou64_full_empty(void) diff --git a/util/cutils.c b/util/cutils.c index 8bacf349383..83948926ec9 100644 --- a/util/cutils.c +++ b/util/cutils.c @@ -384,12 +384,13 @@ static int check_strtox_error(const char *nptr, char *ep, * * @nptr may be null, and no conversion is performed then. * - * If no conversion is performed, store @nptr in *@endptr and return - * -EINVAL. + * If no conversion is performed, store @nptr in *@endptr, 0 in + * @result, and return -EINVAL. * * If @endptr is null, and the string isn't fully converted, return - * -EINVAL. This is the case when the pointer that would be stored in - * a non-null @endptr points to a character other than '\0'. + * -EINVAL with @result set to the parsed value. This is the case + * when the pointer that would be stored in a non-null @endptr points + * to a character other than '\0'. * * If the conversion overflows @result, store INT_MAX in @result, * and return -ERANGE. @@ -407,6 +408,7 @@ int qemu_strtoi(const char *nptr, const char **endptr, int base, assert((unsigned) base <= 36 && base != 1); if (!nptr) { + *result = 0; if (endptr) { *endptr = nptr; } @@ -436,12 +438,13 @@ int qemu_strtoi(const char *nptr, const char **endptr, int base, * * @nptr may be null, and no conversion is performed then. * - * If no conversion is performed, store @nptr in *@endptr and return - * -EINVAL. + * If no conversion is performed, store @nptr in *@endptr, 0 in + * @result, and return -EINVAL. * * If @endptr is null, and the string isn't fully converted, return - * -EINVAL. This is the case when the pointer that would be stored in - * a non-null @endptr points to a character other than '\0'. + * -EINVAL with @result set to the parsed value. This is the case + * when the pointer that would be stored in a non-null @endptr points + * to a character other than '\0'. * * If the conversion overflows @result, store UINT_MAX in @result, * and return -ERANGE. @@ -460,6 +463,7 @@ int qemu_strtoui(const char *nptr, const char **endptr, int base, assert((unsigned) base <= 36 && base != 1); if (!nptr) { + *result = 0; if (endptr) { *endptr = nptr; } @@ -495,12 +499,13 @@ int qemu_strtoui(const char *nptr, const char **endptr, int base, * * @nptr may be null, and no conversion is performed then. * - * If no conversion is performed, store @nptr in *@endptr and return - * -EINVAL. + * If no conversion is performed, store @nptr in *@endptr, 0 in + * @result, and return -EINVAL. * * If @endptr is null, and the string isn't fully converted, return - * -EINVAL. This is the case when the pointer that would be stored in - * a non-null @endptr points to a character other than '\0'. + * -EINVAL with @result set to the parsed value. This is the case + * when the pointer that would be stored in a non-null @endptr points + * to a character other than '\0'. * * If the conversion overflows @result, store LONG_MAX in @result, * and return -ERANGE. @@ -517,6 +522,7 @@ int qemu_strtol(const char *nptr, const char **endptr, int base, assert((unsigned) base <= 36 && base != 1); if (!nptr) { + *result = 0; if (endptr) { *endptr = nptr; } @@ -537,12 +543,13 @@ int qemu_strtol(const char *nptr, const char **endptr, int base, * * @nptr may be null, and no conversion is performed then. * - * If no conversion is performed, store @nptr in *@endptr and return - * -EINVAL. + * If no conversion is performed, store @nptr in *@endptr, 0 in + * @result, and return -EINVAL. * * If @endptr is null, and the string isn't fully converted, return - * -EINVAL. This is the case when the pointer that would be stored in - * a non-null @endptr points to a character other than '\0'. + * -EINVAL with @result set to the parsed value. This is the case + * when the pointer that would be stored in a non-null @endptr points + * to a character other than '\0'. * * If the conversion overflows @result, store ULONG_MAX in @result, * and return -ERANGE. @@ -560,6 +567,7 @@ int qemu_strtoul(const char *nptr, const char **endptr, int base, assert((unsigned) base <= 36 && base != 1); if (!nptr) { + *result = 0; if (endptr) { *endptr = nptr; } @@ -588,6 +596,7 @@ int qemu_strtoi64(const char *nptr, const char **endptr, int base, assert((unsigned) base <= 36 && base != 1); if (!nptr) { + *result = 0; if (endptr) { *endptr = nptr; } @@ -613,6 +622,7 @@ int qemu_strtou64(const char *nptr, const char **endptr, int base, assert((unsigned) base <= 36 && base != 1); if (!nptr) { + *result = 0; if (endptr) { *endptr = nptr; } -- 2.40.1